A crane collapsed on the Grand Mosque in the Muslim holy city of Mecca in Saudi Arabia Friday killing at least 87 people and wounding over 180 others, government officials revealed.

Images from the scene depict of a huge red crane crashed through the mosque's roof, and despite reports that high winds and rain were the cause of the incident, the real reason for the collapse is still unknown, according to The Guardian.

Various cranes surround the mosque in order to support an ongoing expansion to increase the area of the mosque by 4.3 million square feet, to allow it to accommodate up to 2.2 million at once, according to the BBC.

Saudi Arabia's civil defense authority provided a series of rising casualty numbers on its official Twitter account. According to a tweet it posted, the wounded count is at 184, but that number is expected to rise.

Other tweets from within the mosque show a bloody scene with police and witnesses attending to bloodied bodies strewn across the floor, according to the Associated Press.

The mosque is Islam's most sacred site and the destination for millions of Muslims undertaking the Hajj pilgrimage every year.

Islam requires that every Muslim who is capable of doing so, make one pilgrimage to the holy site at least once during their lifetime. Upon reaching the site, pilgrims perform a "tawaf" where they walk seven times around the Kaaba, a black cube-shaped building in the heart of the mosque, in a counter-clockwise direction.